The Impact

Summary

Scientists at the University of California, Los Angeles–based EFRC, Molecularly Engineered Energy Materials, have developed a novel approach to synthesize nanostructured high performance electrodes useful for the next generation lithium ion batteries. By directly coating active nanocrystals onto pre-formed three-dimensional conducting carbon nanotube (CNT) scaffolds, the need for the binders for structural stability at the nanostructured interfaces was eliminated – an important advance since binders can decrease the overall battery performance. Use of nanometer-sized particles in electrodes drastically reduces the charging times of batteries and supercapacitors because their high surface area offers ample sites for rapid movement of lithium ions, the material that carries the electrical charge. This conformal coating method provides critical features for high-performance electrodes, including effective pathways for electronic transport, high active-material loading, structural robustness and mechanical flexibility due to the excellent intrinsic properties of the CNT scaffold and the high surface area and shortened lithium-diffusion length of the nanocrystals. Electrodes based on titanium dioxide nanocrystals charged to 80% of full capacity in 5 minutes and showed negligible energy loss after a few hundred cycles.